Martin Walsh 1 | 15/09/2012 22:11:08 |
113 forum posts 2 photos |
Excuse my very crude drawing would this work ok as a very simple quick change tool holder I remember seeing something similer many years ago but couldnt find any thing on the net I just wanted to make it up in a day and use it on my s7 Best Wishes Martin Edited By Martin Walsh 1 on 15/09/2012 22:17:25 |
John Stevenson | 15/09/2012 23:29:53 |
![]() 5068 forum posts 3 photos | Martin, Not the best design as it pushes so it's only relying on the two dovetail faces.
If you want to keep it simple, scrap the two push screws in the post and fit two screws in the holder one above the other. Drill and tap them in the face just above the OL in holder, this way it will grip on 4 faces and pull back in to the dovetail.
A better design would be to reverse the dovetails, dril the same toe screw holes as above but now drill them into the post and fits a gib strip for the screws to push on. Advantage of this is only two hles to drill and tap instaed of in every holder and the holders wil be easier to make given that they are open dovetails which means you can use angles side and face milling cutters instaed of fraginle dovetail cutters.
Edited By John Stevenson on 15/09/2012 23:43:18 |
Flying Fifer | 15/09/2012 23:38:54 |
180 forum posts | Hi, Yes it probably would but personally I`d fit longer bolts with a locknut under the head. The similar one was probably John Stevenson`s which was in M. E. 1998 Vol 181 issue 4080. I made one & can recommend it. Regards Alan |
Flying Fifer | 15/09/2012 23:40:50 |
180 forum posts | You just home from the pub John ?? |
Martin Walsh 1 | 16/09/2012 10:51:02 |
113 forum posts 2 photos | Thanks John that looks a lot more sturdier and the way to go Thanks for your advice I am going to pop down to the shed and see if I can find something in the scrap box to make it up
I might even be brave and try to do the dovetail on the shaping machine Best Wishes Martin |
Stub Mandrel | 16/09/2012 11:02:25 |
![]() 4318 forum posts 291 photos 1 articles | Having just made a QCTP, I wondered about this too. The contact area of the dovetails is 0.625 square inches. Add the area of the piston (on my design) and the area is about 0.95 square inches. The contact area of a typical 2" long 5/16" HSS tool is 0.625 square inches. The contact area of the clamp screws is less than that of the piston. So perhaps anything that further increases the contact area is over-engineering? Neil
|
SverreE | 16/09/2012 17:33:31 |
22 forum posts 14 photos | Hello; I posted this recently in another thread, but I think you should have a look at links below - this QCTP is really simple! I bought plans to make a QCTP which is available as a kit (or only drawings) from METAL LATHE in USA, the MLA-23. This seems to be a very nice design, simple and stable. See the following link: The design is also described in the "Home Shop Machinist" May/June 2006, and also a brilliant description in the "Practical Machinist" forum: Since I live in Norway, I ordered only the drawings from METAL LATHE, due to the cost of shipping the heavy hardware from USA.
Regards Sverre |
Michael Gilligan | 17/09/2012 07:35:26 |
![]() 23121 forum posts 1360 photos | Sverre, Thanks for re-posting those links The design looks very promising; and that write-up about building it is exemplary. Definitely one to remember !! MichaelG. |
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
Sign up to our newsletter and get a free digital issue.
You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.